At 2004-04-20 06:44 PM -0700, you wrote:
>Oh no, no mutable state! Purely static data and static methods.
>What I have coils down to something like this:
>>class Terrain( pb.Copyable, pb.RemoteCopy ):
> def moveCost( cls, unit ):
> return cls.cost
> moveCost = classmethod( moveCost )
>>class Mountains( Terrain ):
> cost = 6
>>>A bunch of hexes then have their .terrain = Mountains (etc.) I could easily
>change this to instantiation the various Terrains, but in my mind that
>implies that an instance's state could differ. I'm beginning to think
>the distinction is more trouble than it's worth however, and potentially
>confusing.
...and...
>I have a dictionary of hexes keyed by their grid location.
>>map.cells = {(1,1):hexCellInstance, ...}
>>Each of these cells has a .terrain, which is a reference to a Terrain
>subclass. These have static data and methods, for use by various game
>algorithms, e.g. how far can unit Foo move through Mountains.
>>On each turn a (filtered) version of this state is passed to game clients,
>so that they can view it, validate their orders against it, etc.
How about making Mountains, Plains, etc. Singletons?
Then, instead of assigning hexCellInstance.terrain=Mountain,
you assign hexCellInstance.terrain=Mountain() (note the
parentheses!). At that point, each cell.terrain is an object
reference instead of a class reference and (IIUC) should
remote-copy properly.
Caveat: I've not used pb; this is based on my *very* weak
understanding (misunderstanding?) of it. In particular,
I don't know how pb/copyable would interact with a singleton.
I would *expect* that the remote unserialization would
(eventually) invoke Mountains.__call__ and get a reference
to the corresponding singleton on the client side.
class Singleton(type):
def __init__( cls, name, bases, classdict ):
super( Singleton, cls ).__init__( name, bases, classdict )
cls.instance = None
def __call__( cls, *args, **kw ):
if cls.instance is None:
cls.instance = super( Singleton, cls ).__call__( *args, **kw )
return cls.instance
class Mountains( Terrain ):
__metaclass__ = Singleton
cost = 6
- Sam
__________________________________________________________
Spinward Stars, LLC Samuel Reynolds
Software Consulting and Development 303-805-1446
http://SpinwardStars.com/sam at SpinwardStars.com